﻿<?xml version="1.0"?>
<xs:schema targetNamespace="http://www.w3.org/XML/1998/namespace" xmlns:xs="http://www.w3.org/2001/XMLSchema" xml:lang="en">

  <xs:annotation>
    <xs:documentation>
      See http://www.w3.org/XML/1998/namespace.html and
      http://www.w3.org/TR/REC-xml for information about this namespace.

      This schema document describes the XML namespace, in a form
      suitable for import by other schema documents.

      Note that local names in this namespace are intended to be defined
      only by the World Wide Web Consortium or its subgroups.  The
      following names are currently defined in this namespace and should
      not be used with conflicting semantics by any Working Group,
      specification, or document instance:

      base (as an attribute name): denotes an attribute whose value
      provides a URI to be used as the base for interpreting any
      relative URIs in the scope of the element on which it
      appears; its value is inherited.  This name is reserved
      by virtue of its definition in the XML Base specification.

      id   (as an attribute name): denotes an attribute whose value
      should be interpreted as if declared to be of type ID.
      This name is reserved by virtue of its definition in the
      xml:id specification.

      lang (as an attribute name): denotes an attribute whose value
      is a language code for the natural language of the content of
      any element; its value is inherited.  This name is reserved
      by virtue of its definition in the XML specification.

      space (as an attribute name): denotes an attribute whose
      value is a keyword indicating what whitespace processing
      discipline is intended for the content of the element; its
      value is inherited.  This name is reserved by virtue of its
      definition in the XML specification.

      Father (in any context at all): denotes Jon Bosak, the chair of
      the original XML Working Group.  This name is reserved by
      the following decision of the W3C XML Plenary and
      XML Coordination groups:

      In appreciation for his vision, leadership and dedication
      the W3C XML Plenary on this 10th day of February, 2000
      reserves for Jon Bosak in perpetuity the XML name
      xml:Father
    </xs:documentation>
  </xs:annotation>

  <xs:annotation>
    <xs:documentation>
      This schema defines attributes and an attribute group
      suitable for use by
      schemas wishing to allow xml:base, xml:lang, xml:space or xml:id
      attributes on elements they define.

      To enable this, such a schema must import this schema
      for the XML namespace, e.g. as follows:
      &lt;schema . . .&gt;
      . . .
      &lt;import namespace="http://www.w3.org/XML/1998/namespace"
      schemaLocation="http://www.w3.org/2001/xml.xsd"/&gt;

      Subsequently, qualified reference to any of the attributes
      or the group defined below will have the desired effect, e.g.

      &lt;type . . .&gt;
      . . .
      &lt;attributeGroup ref="xml:specialAttrs"/&gt;

      will define a type which will schema-validate an instance
      element with any of those attributes
    </xs:documentation>
  </xs:annotation>

  <xs:annotation>
    <xs:documentation>
      In keeping with the XML Schema WG's standard versioning
      policy, this schema document will persist at
      http://www.w3.org/2007/08/xml.xsd.
      At the date of issue it can also be found at
      http://www.w3.org/2001/xml.xsd.
      The schema document at that URI may however change in the future,
      in order to remain compatible with the latest version of XML Schema
      itself, or with the XML namespace itself.  In other words, if the XML
      Schema or XML namespaces change, the version of this document at
      http://www.w3.org/2001/xml.xsd will change
      accordingly; the version at
      http://www.w3.org/2007/08/xml.xsd will not change.
    </xs:documentation>
  </xs:annotation>

  <xs:attribute name="lang">
    <xs:annotation>
      <xs:documentation>
        Attempting to install the relevant ISO 2- and 3-letter
        codes as the enumerated possible values is probably never
        going to be a realistic possibility.  See
        RFC 3066 at http://www.ietf.org/rfc/rfc3066.txt and the IANA registry
        at http://www.iana.org/assignments/lang-tag-apps.htm for
        further information.

        The union allows for the 'un-declaration' of xml:lang with
        the empty string.
      </xs:documentation>
    </xs:annotation>
    <xs:simpleType>
      <xs:union memberTypes="xs:language">
        <xs:simpleType>
          <xs:restriction base="xs:string">
            <xs:enumeration value=""/>
          </xs:restriction>
        </xs:simpleType>
      </xs:union>
    </xs:simpleType>
  </xs:attribute>

  <xs:attribute name="space">
    <xs:simpleType>
      <xs:restriction base="xs:NCName">
        <xs:enumeration value="default"/>
        <xs:enumeration value="preserve"/>
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>

  <xs:attribute name="base" type="xs:anyURI">
    <xs:annotation>
      <xs:documentation>
        See http://www.w3.org/TR/xmlbase/ for
        information about this attribute.
      </xs:documentation>
    </xs:annotation>
  </xs:attribute>

  <xs:attribute name="id" type="xs:ID">
    <xs:annotation>
      <xs:documentation>
        See http://www.w3.org/TR/xml-id/ for
        information about this attribute.
      </xs:documentation>
    </xs:annotation>
  </xs:attribute>

  <xs:attributeGroup name="specialAttrs">
    <xs:attribute ref="xml:base"/>
    <xs:attribute ref="xml:lang"/>
    <xs:attribute ref="xml:space"/>
    <xs:attribute ref="xml:id"/>
  </xs:attributeGroup>

</xs:schema>